Olive-green sulfur dye and process of making same.



UNlTE rarus Patented June 2, 1903,

ruins.

AUGUST LEOPOLD LASKA, OF OFFENBAOH-ON-THE-MAIN, GERMANY, AS-

SIGNOR TO THE FIRM OF K OEHLER, ANILIN- 85 ANILINFARBEN FABRIK, OF OFFENBAOH-ON-THE-"WAIN, GERMANY.

OLIVE-GREEN SULFUR DYE AND PROCESS OFlVIAKING SAME.

SPECIFICATION forming part of Letters Patent No. 729,874, dated June 2, 1903.

Application filed March 3, 1903. Serial No. 145,988. (No-specimens.)

purposes.

To cLZZ whom it may concern.- I

Be it known that I, "AUGUST LEOPOL LASKA, doctor of philosophy, chemist, residing at 44 Gerberstrasse, Offenbach-on-the-Main, Germany, have invented new and useful Improvements in Olive-Green Sulfur Dyes, of which the following is a specification.

I have found that by treating diformylmeta-phenylendiamin with sulfur and sodium sulfid under suitable conditions very valuable dyestuffs of a great coloring power are obtained which dye cotton in a bath containing sodium sulfid olive-green shades very fast to light and soap. If a condensing agent is added to the melt-for instance, salts of heavy metals-theproperties of the resulting coloring matters may be improved. Thus by adding 'zinc chlorid a dyestulf of a purer and more greenish tinge is obtained.

Trials to make sulfur dyes from acidulated meta-phenylendiamin have not been successful, as the products are of a feeble dyeing power and dye dim green-gray shades.

The diformyl-meta-phenylendiamin may be prepared in an easy manner, as described by Tobias in the Berichie der Deuvischen Chemischen Gesellschotft, XV 24.47.

The following is an example 110w to carry out my process; but I do not confine myself to the directions given, as they may be varied Within wide limits without essentially altering the result. The parts are by weight, and the temperature degrees refer to the centigrade scale: Take two hundred and twentyfive parts of crystals of sodium sulfid, one hundred parts of sulfur, and fifteen parts of water and melt the whole mass until the complete fusion of the sulfur. Then at a temperature of 110 introduce a mixture of fifty parts of diformyl-meta-phenylendiamin and seven parts of zinc chlorid. Raise the temperatdre gradually to about 230, continue heating to finally 275 until no more dyestufi is formed. After cooling the melt is powdered and can be used directly for dyeing The shades are purer and more greenish than those of other olive sulfur dyes actually in trade.

When carrying out the process without the aid of zinc chlorid, the greenish shade is not so bright.

The new dyestuff is easily soluble in water with a yellowish-green color and in concentrated sulfuric acid with a dirty-green color. On adding hydrochloric acid to the aqueous solution a yellowish-brown precipitate falls down which is soluble in diluted soda-lye and in diluted ammonia.

Now what I claim, and desire to secure by Letters Patent, is the following:

1. The process for the production of olivegreen cotton dyestuffs by melting together diforlnyl-meta-phenylendiamin with sulfur and sodium sulfid.

2. The process for the production of olive green cotton dyestuffs by melting together diformyl-meta-phenylendiamin with sulfur and sodium sulfid simultaneously with salts of heavy metals.

3. The process for the production of olivegreen cotton dyestuffs by melting together diformyl-meta-phenylendiamin with sulfur and sodium sulfid in the presence of zinc chlorid.

4. Asa new article of manufacture the dyestuff which is obtained by melting together diformyl-meta-phenylendiamin with sulfur and sodium sulfid in the presence of zinc chlorid, forming a black brittle mass, which may easily be powdered and which dissolves in concentrated sulfuric acid to a dirty-green, and in water to a greenish-yellow solution from which hydrochloric acid separates a yellowish-brown precipitate, which is soluble in diluted soda-lye and in diluted ammonia all substantially as hereinbefore described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

AUGUST LEOPOLD LASKA.

Witnesses EVA SAITLER, HERMANN WEIL. 

